The electrical equipment in the computer industry typically uses internally and externally-threaded loose standoffs, spacer washers, lock washers and nuts to attach the electrical receptacle to the chassis and then the plug to the receptacle. FIG. 1 shows a typical assembly of parts found at the rear of the chassis for connecting incoming and outgoing electrical data cables. The connectors are multiple pin-and-socket receptacles and plugs which electrically interconnect and attach the data transmission cables from the computer chassis to related peripheral devices, such as printers, plotters or other computers. These connectors have a modified elongated "D" shape to ensure orientation in their mounting holes and also orientation with the mating plugs. They have become known as "D" connectors. Pin configuration shell sizes, mounting holes, and the like have been standardized throughout the world and all manufacturers meet these standards.
Because it was never anticipated that the chassis panel connectors would be used in the volume in which they are manufactured today, no attempt in the past has been made at using other than loose hardware to either attach the receptacle to the chassis or to attach the plug to the receptacle. The standardized mounting hole diameter cutout size, and center-to-center distance were established using loose hardware, typically a #40 screw and nut. Previous attempts at eliminating the loose hardware to provide fewer number of parts by using, for instance, permanently installed self-clinching fasteners in the existing chassis mounting holes met with failure due to the very minimal spacing between the screw hole and the connector cutout in the panel. To date, no attempt has been successful in installing a standoff into the chassis due to this limited edge distance.
Furthermore, there exists a problem in the art with accommodating different chassis panel thicknesses. It is important that the mounting flanges of the mating receptacle and plug be fastened the proper distance apart. If the length of the mounting standoff is too great, the plug will not be inserted deeply enough into the receptacle, thereby jeopardizing a proper electrical connection. On the other hand, if the length of the standoff is too short, the plug will bottom out against the receptacle and the plug flange may be bent or broken as the plug screw is tightened down to the shoulder of the standoff. Because in the existing art the standoff is located between the outside face of the panel and the plug, a change in panel thickness will vary the plug/receptacle spacing. In order to achieve the proper standoff distance from the outside face of the panel, it is the usual practice in the art to vary the standoff length by adding or subtracting loose washers, such as those shown in FIG. 1.